一.在eclipse中使用Graphviz：建立一个 class Graphviz
GraphViz库的代码如下（复制到class GraphViz中）
1//GraphViz.java - a simple API to call dot from Java programs 2/*$Id$*/ 3/* 4****************************************************************************** 5* * 6* (c) Copyright 2003 Laszlo Szathmary * 7* * 8* This program is free software; you can redistribute it and/or modify it * 9* under the terms of the GNU Lesser General Public License as published by * 10* the Free Software Foundation; either version 2.1 of the License, or * 11* (at your option) any later version. * 12* * 13* This program is distributed in the hope that it will be useful, but * 14* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY * 15* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public * 16* License for more details. * 17* * 18* You should have received a copy of the GNU Lesser General Public License * 19* along with this program; if not, write to the Free Software Foundation, * 20* Inc., 675 Mass Ave, Cambridge, MA 02139, USA. * 21* * 22****************************************************************************** 23*/ 24 25import java.io.BufferedReader; 26import java.io.DataInputStream; 27import java.io.File; 28import java.io.FileInputStream; 29import java.io.FileOutputStream; 30import java.io.FileWriter; 31import java.io.InputStreamReader; 32 33/** 34* <dl> 35* <dt>Purpose: GraphViz Java API 36* <dd> 37* 38* <dt>Description: 39* <dd> With this Java class you can simply call dot 40* from your Java programs 41* <dt>Example usage: 42* <dd> 43* <pre> 44* GraphViz gv = new GraphViz(); 45* gv.addln(gv.start_graph()); 46* gv.addln("A -> B;"); 47* gv.addln("A -> C;"); 48* gv.addln(gv.end_graph()); 49* System.out.println(gv.getDotSource()); 50* 51* String type = "gif"; 52* File out = new File("out." + type); // out.gif in this example 53* gv.writeGraphToFile( gv.getGraph( gv.getDotSource(), type ), out ); 54* </pre> 55* </dd> 56* 57* </dl> 58* 59* @version v0.4, 2011/02/05 (February) -- Patch of Keheliya Gallaba is added. Now you 60* can specify the type of the output file: gif, dot, fig, pdf, ps, svg, png, etc. 61* @version v0.3, 2010/11/29 (November) -- Windows support + ability 62* to read the graph from a text file 63* @version v0.2, 2010/07/22 (July) -- bug fix 64* @version v0.1, 2003/12/04 (December) -- first release 65* @author Laszlo Szathmary (<a href="jabba.laci@gmail.com">jabba.laci@gmail.com</a>) 66*/ 67public class Graphviz 68{ 69/** 70 * The dir. where temporary files will be created. 71 */ 72//private static String TEMP_DIR = "/tmp"; // Linux 73private static String TEMP_DIR = "c:/temp"; // Windows 74 75/** 76 * Where is your dot program located? It will be called externally. 77 */ 78// private static String DOT = "/usr/bin/dot"; // Linux 79private static String DOT = "C:\\Program Files (x86)\\Graphviz2.38\\bin\\dot.exe"; // Windows 80 81/** 82 * The source of the graph written in dot language. 83 */ 84private StringBuilder graph = new StringBuilder(); 85 86/** 87 * Constructor: creates a new GraphViz object that will contain 88 * a graph. 89 */ 90public Graphviz() { 91} 92 93/** 94 * Returns the graph's source description in dot language. 95 * @return Source of the graph in dot language. 96 */ 97public String getDotSource() { 98 return graph.toString(); 99} 100 101/** 102 * Adds a string to the graph's source (without newline). 103 */ 104public void add(String line) { 105 graph.append(line); 106} 107 108/** 109 * Adds a string to the graph's source (with newline). 110 */ 111public void addln(String line) { 112 graph.append(line + "\n"); 113} 114 115/** 116 * Adds a newline to the graph's source. 117 */ 118public void addln() { 119 graph.append('\n'); 120} 121 122/** 123 * Returns the graph as an image in binary format. 124 * @param dot_source Source of the graph to be drawn. 125 * @param type Type of the output image to be produced, e.g.: gif, dot, fig, pdf, ps, svg, png. 126 * @return A byte array containing the image of the graph. 127 */ 128public byte[] getGraph(String dot_source, String type) 129{ 130 File dot; 131 byte[] img_stream = null; 132 133 try { 134 dot = writeDotSourceToFile(dot_source); 135 if (dot != null) 136 { 137 img_stream = get_img_stream(dot, type); 138 if (dot.delete() == false) 139 System.err.println("Warning: " + dot.getAbsolutePath() + " could not be deleted!"); 140 return img_stream; 141 } 142 return null; 143 } catch (java.io.IOException ioe) { return null; } 144} 145 146/** 147 * Writes the graph's image in a file. 148 * @param img A byte array containing the image of the graph. 149 * @param file Name of the file to where we want to write. 150 * @return Success: 1, Failure: -1 151 */ 152public int writeGraphToFile(byte[] img, String file) 153{ 154 File to = new File(file); 155 return writeGraphToFile(img, to); 156} 157 158/** 159 * Writes the graph's image in a file. 160 * @param img A byte array containing the image of the graph. 161 * @param to A File object to where we want to write. 162 * @return Success: 1, Failure: -1 163 */ 164public int writeGraphToFile(byte[] img, File to) 165{ 166 try { 167 FileOutputStream fos = new FileOutputStream(to); 168 fos.write(img); 169 fos.close(); 170 } catch (java.io.IOException ioe) { ioe.printStackTrace();return -1; } 171 return 1; 172} 173 174/** 175 * It will call the external dot program, and return the image in 176 * binary format. 177 * @param dot Source of the graph (in dot language). 178 * @param type Type of the output image to be produced, e.g.: gif, dot, fig, pdf, ps, svg, png. 179 * @return The image of the graph in .gif format. 180 */ 181private byte[] get_img_stream(File dot, String type) 182{ 183 File img; 184 byte[] img_stream = null; 185 186try { 187 img = File.createTempFile("graph_", "."+type, new File(Graphviz.TEMP_DIR)); 188 Runtime rt = Runtime.getRuntime(); 189 190 // patch by Mike Chenault 191 String[] args = {DOT, "-T"+type, dot.getAbsolutePath(), "-o", img.getAbsolutePath()}; 192 Process p = rt.exec(args); 193 194 p.waitFor(); 195 196FileInputStream in = new FileInputStream(img.getAbsolutePath()); 197 img_stream = new byte[in.available()]; 198 in.read(img_stream); 199 // Close it if we need to 200 if( in != null ) in.close(); 201 202if (img.delete() == false) 203 System.err.println("Warning: " + img.getAbsolutePath() + " could not be deleted!"); 204 } 205 catch (java.io.IOException ioe) { 206 System.err.println("Error: in I/O processing of tempfile in dir " + Graphviz.TEMP_DIR+"\n"); 207 System.err.println(" or in calling external command"); 208 ioe.printStackTrace(); 209 } 210 catch (java.lang.InterruptedException ie) { 211 System.err.println("Error: the execution of the external program was interrupted"); 212 ie.printStackTrace(); 213 } 214 215return img_stream; } 216/** 217 * Writes the source of the graph in a file, and returns the written file 218 * as a File object. 219 * @param str Source of the graph (in dot language). 220 * @return The file (as a File object) that contains the source of the graph. 221 */ 222public File writeDotSourceToFile(String str) throws java.io.IOException 223{ 224 File temp; 225 try { 226 temp = File.createTempFile("graph_", ".dot.tmp", new File(Graphviz.TEMP_DIR)); 227 FileWriter fout = new FileWriter(temp); 228 fout.write(str); 229 fout.close(); 230 } 231 catch (Exception e) { 232 System.err.println("Error: I/O error while writing the dot source to temp file!"); 233 return null; 234 } 235 return temp; 236} 237 238/** 239 * Returns a string that is used to start a graph. 240 * @return A string to open a graph. 241 */ 242public String start_graph() { 243 return "digraph G {" ; 244} 245 246/** 247 * Returns a string that is used to end a graph. 248 * @return A string to close a graph. 249 */ 250public String end_graph() { 251 return "}"; 252} 253 254/** 255 * Read a DOT graph from a text file. 256 * 257 * @param input Input text file containing the DOT graph 258 * source. 259 */ 260public void readSource(String input) 261{ 262 StringBuilder sb = new StringBuilder(); 263 264 try 265 { 266 FileInputStream fis = new FileInputStream(input); 267 DataInputStream dis = new DataInputStream(fis); 268 BufferedReader br = new BufferedReader(new InputStreamReader(dis)); 269 String line; 270 while ((line = br.readLine()) != null) { 271 sb.append(line); 272 } 273 dis.close(); 274 } 275 catch (Exception e) { 276 System.err.println("Error: " + e.getMessage()); 277 } 278 279 this.graph = sb; 280} 281 282} // end of class GraphViz
二.使用GraphViz库画图，GraphViz画图代码示例见https://www.2cto.com/kf/201212/173431.html
测试代码如下：
1import java.io.File; 2 3public class GTest { 4 public static void main(String[] args){ 5 GTest gtest = new GTest(); 6 String[] nodes = {"A","B","C","D","E","F","G"}; 7 String[] preline = {"B -> A","D -> B","E -> D","C -> E","G -> C","F -> G"}; 8 gtest.start(nodes, preline); 9 } 10 private void start(String[] nodes,String[] preline){ 11 12 Graphviz gv = new Graphviz(); 13 //定义每个节点的style 14 String nodesty = "[shape = polygon, sides = 6, peripheries = 2, color = lightblue, style = filled]"; 15 //String linesty = "[dir=\"none\"]"; 16 17 gv.addln(gv.start_graph());//SATRT 18 gv.addln("edge[fontname=\"DFKai-SB\" fontsize=15 fontcolor=\"black\" color=\"brown\" style=\"filled\"]"); 19 gv.addln("size =\"8,8\";"); 20 //设置节点的style 21 for(int i=0;i<nodes.length;i++){ 22 gv.addln(nodes[i]+" "+nodesty); 23 } 24 for(int i=0;i<preline.length;i++){ 25 gv.addln(preline[i]+" "+" [dir=\"none\"]"); 26 } 27 gv.addln(gv.end_graph());//END 28 //节点之间的连接关系输出到控制台 29 System.out.println(gv.getDotSource()); 30 //输出什么格式的图片(gif,dot,fig,pdf,ps,svg,png,plain) 31 String type = "png"; 32 //输出到文件夹以及命名 33 File out = new File("C:/Users/fanghui/Desktop/GraphTest/test." + type); // Linux 34 //File out = new File("c:/eclipse.ws/graphviz-java-api/out." + type); // Windows 35 gv.writeGraphToFile( gv.getGraph( gv.getDotSource(), type ), out ); 36 } 37}
三.结果：
控制台输出
输出生成的图片
